The Ordnance Survey's first edition six-inch map, surveyed in 1841, marks the spot with the word "cave", a notation cartographers of that era typically used to indicate a souterrain. A souterrain is an artificially constructed underground passage or chamber, usually built during the early medieval period and associated with nearby settlement, most often used for storage or as a place of refuge. When a surveyor returned to the site in 1985, no surface trace of it remained visible.

The souterrain appears to have sat within the interior of a ringfort, the circular earthwork enclosure that was the standard form of rural settlement in early medieval Ireland. Ringforts often contained souterrains beneath their floors or banks, and the combination of the two features at this site is consistent with that pattern. The 1841 map gives the clearest record of what was once here, or at least of what was once apparent at ground level. Whether the souterrain has collapsed inward, silted up entirely, or simply been obscured by over a century of agricultural use on the sloping pasture, the 1985 survey could not say.